The present invention relates to a method for measuring mitochondrial activity. Moreover, the present invention relates to a diagnostic kit for measuring platelet mitochondrial activity.
As is known, Reactive Oxygen Species (ROS) play a fundamental role in pathological processes. Their chemical aggression towards all biological macromolecules causes a deterioration in cell structures which has been suggested to be the cause or pathogenic event leading to many degenerative diseases, cancer and ageing. In order to understand ROS biochemistry and pathology, research focuses chiefly on mitochondrions, since these are important ROS producers in the respiratory chain and are particularly vulnerable in the sophisticated mechanism of oxidative phosphorylation. The mitochondrial ageing theory is based on the idea that cells which are constantly exposed to ROS are gradually damaged, particularly through random errors in the mitochondrial DNA, in their energy functions, with a gradual loss of efficiency and consequent cell death.
In light of the above, ageing and age-related illnesses in humans must take into account mitochondrial activity. This activity can be directly investigated only in cells containing mitochondria, for example platelets. Blood platelets are a particularly suitable system, since the platelets contain mitochondria and are easily collected using a non-invasive technique.
As is known, platelets obtain the energy which allows them to function partly from glycolysis and partly from mitochondrial oxidative phosphorylation. The most important function is the aggregation process, part of the blood coagulation mechanism, and physiologically a result of stimulation and exocytosis of their secretion granules. The aggregation of platelets requires energy, conserved in the form of ATP generated by both the glycolysis and the oxidative phosphorylation. Inhibition of the respiratory chain partially inhibits platelet aggregation, indicating that the function is mainly, but not completely, provided with energy by the glycolytic ATP.
Therefore, a method is still required for measuring mitochondrial activity. In particular, a method is required for measuring the mitochondrial activity using platelets. More specifically, a method is required for measuring mitochondrial activity by measuring the amount of glycolytic and mitochondrial ATP in the platelets.
The use of platelets as markers for mitochondrial lesions is due to the fact that the alterations which accompany ageing and age-related illnesses are present in all cells and, therefore, platelets can indicate general bioenergetic changes.